Successful treatment and long-term follow-up of a young cat with feline infectious peritonitis and renal lymphoma.

BACKGROUND

Feline lymphoma is often a fatal disease, and achieving a cure with chemotherapy is questionable. Feline infectious peritonitis (FIP) diagnosis was historically associated with a poor prognosis and high mortality, but remission is possible with the newly available treatment. Long-term follow-up data on treated patients remain limited.

CASE DESCRIPTION: A 3.9-year-old neutered male cat presented with hyporexia and lethargy lasting for several days. An abdominal mass was palpated on clinical examination and confirmed to be a renal mass on a computed tomography angiography scan. Ultrasound-guided fine needle aspirates and cytological evaluation revealed a large-cell renal lymphoma. A modified Cyclophosphamide, vincristine and prednisolone protocol with vinblastine addition (Cyclophosphamide, vincristine, prednisolone and vinblastine protocol) was started, resulting in a complete response. Twenty weeks after chemotherapy initiation, the cat developed anorexia, fever, and pleural effusion. FIP was diagnosed based on a positive reverse transcription polymerase chain reaction test from the pleural effusion. Subcutaneous administration of GS441524 led to FIP resolution.

CONCLUSION

The cat did not receive any further treatment for both FIP and lymphoma. Still alive and well, almost 5 years after the diagnosis. To the author's knowledge, this is the first case of renal lymphoma in a cat that subsequently developed FIP. Further studies on the potential correlation between lymphoma, chemotherapy, and FIP are needed.